CN100445148C - Method and device for assisting a motor vehicle server for the vehicle stabilisation - Google Patents

Abstract

The invention relates to a method for assisting a vehicle server in order to stabilise the vehicle consisting in supplying the vehicle steering cable with an additional steering moment. The inventive method is characterised in that the first part of an additional steering moment is determined according to a steering angle difference between the momentary steering angle on the steerable wheels of the vehicle and a reference steering angle, the steering angle difference is determined according to the difference between the momentary value of a sheer rate of the vehicle and the reference sheer rate value and the reference sheer rate value is determined by means of the value of at least one quantity which is predetermined by a driver on a vehicle model. An appropriate device for carrying out said method is also disclosed.

Description

The method and the device that are used for the operator of service vehicle when stablizing vehicle

Technical field

The present invention relates to a kind of method that is used for the operator of service vehicle when stablizing vehicle, load with the steering system of additional steering torque in the method this vehicle.

In addition, the invention still further relates to a kind of device that is used for the operator of service vehicle, this device comprises and being used for the mechanism of additional steering torque to the steering system loading of vehicle.

Background technology

Many modern vehicle have been equipped yaw velocity control setup (ESP), and this yaw velocity control setup is stablized vehicle in critical travel conditions.Thisly be adjusted in this based on according to each wheel and different brake intervention and to the interference of engine control unit is carried out this interference when vehicle performance departs from predetermined target expected performance.This control interfere for vehicle operators be can discover very significantly and be extremely uncomfortable thus, therefore, have only usually and when having determined that there is significant deviation in relative target capabilities, just carry out this control and interfere.

Also known in addition, in critical travel conditions, by the stable deflection angle of motoring condition that makes vehicle is irrespectively regulated in the control interference of vehicle steering device and the steering order (Lenkvorgabe) of vehicle operators.Chaufeur can not feel that this interference is significant obstruction, even and hour can carry out this interference with the deviation of target capabilities thus yet.But must give suitable steering swivel system, for example superposing type steering hardware or the steering-by-wire formula steering hardware of vehicle outfitting for this reason.The danger that exist to take place significantly to hinder the control of mistake of the stability of vehicle to interfere in addition.

Therefore it is desirable for when unsettled rideability begins and especially at the chaufeur only chaufeur of service vehicle that goes as course when handling, and directly do not regulate for example these correction parameters of deflection angle of vehicle.

International Patent Application WO 02/062647 A1 has illustrated a kind of steering swivel system that is used for vehicle, and in this steering swivel system, vehicle operators obtains the tactile data about motoring condition.Here regulate steering torque according to the yaw velocity of vehicle and the deviation between the benchmark yaw velocity by electrical motor, steering hardware is easier to or is difficult to by this steering torque and rotate.

But chaufeur can not obtain concrete indication thus, promptly should how just can make vehicle stabilization when unsettled motoring condition occurring.Especially ham-fisted driver is not for example still known to react in what kind of mode in deficiency or oversteer state and is obtained stable motoring condition.

Summary of the invention

Therefore, the objective of the invention is to, improve the method for the described type of beginning in this wise, that is, make the chaufeur of when stablize vehicle, assisting this vehicle reliably.

The invention provides a kind of method that is used for driver assistance person when stablizing vehicle, load the steering system of this vehicle in the method with additional steering torque, the method is characterized in that, determine first component of this additional steering torque according to the deflection angle deviation between the instantaneous deflection angle on this pivoted wheels on vehicle and specified (expectation) deflection angle, wherein determine this deflection angle deviation according to the deviation between the value of the instantaneous value of the yaw velocity of this vehicle and benchmark yaw velocity, and wherein in an auto model/vehicle, try to achieve the value of this benchmark yaw velocity by the value of the predetermined parameter of chaufeur by means of at least one, wherein, determine a second component of described additional steering torque according to the estimated valve of tire reseting torque, try to achieve described additional steering torque by first component and second component addition.

By such method, can be reliably and driver assistance person when in regulating oversteer situation for example, making the stable specified deflection angle of the motoring condition of this vehicle very effectively.

This benchmark yaw velocity at this preferably according to the rideability of being tried to achieve and considered thus this vehicle by the deflection angle of vehicle operators setting by chaufeur expectation.

But verified here, especially at the vehicle that is equipped with the ESP controller that is used for controlling the yaw velocity deviation, owing to apply this additional steering torque fugitiveness can appear.This may be because chaufeur has influenced this benchmark yaw velocity based on the described auxiliary divertical motion that carries out by means of this additional steering torque.Influencing each other between the value by this additional steering torque and the value of this benchmark yaw velocity can partly cause with this yaw velocity vibration at this, and vehicle is because this vibration and " shaking ".

For fear of this problem, in a favourable form of implementation of the present invention, propose, when the absolute value of the instantaneous yaw velocity of vehicle dropped under the value of the benchmark yaw velocity of trying to achieve in the zero hour of unsettled travel conditions, cancellation should additional steering torque.

Realize stable control thus to vehicle running state.

In another favourable form of implementation of the present invention, propose, determine this deflection angle deviation according to the deviation between the value of the instantaneous value of the yaw velocity of this vehicle and this benchmark yaw velocity, the value of this benchmark yaw velocity was tried to achieve in the zero hour of unsettled travel conditions.

Also can avoid influencing each other and can obtain stable control between the value of the value of this additional steering torque and this benchmark yaw velocity thus.

Preferably determine the zero hour of unstable travel conditions by an enable logic unit.Here suitable is the result of this addressable travel conditions means of identification in enable logic unit.

In another advantageous embodiments of the present invention, propose, determine the second component of this additional steering torque according to the estimated valve of tire reseting torque.

Here by considering this tire reseting torque, can consider and regulate pavement state instantaneous when interfering.Especially obtain in the case for the different tire reseting torque of different surface friction coefficients, the value that should add steering torque thus can be complementary with described friction coefficient.

Preferably by disturbing the parameter sight cell to estimate this tire reseting torque.

In another preferred form of implementation of the present invention, try to achieve this additional steering torque by this first component and this second component addition.

This allows irrelevantly to determine each other from the control component that is somebody's turn to do additional steering torque of described deflection angle deviation derivation and from described tire reseting torque component that try to achieve, that can be counted as interference components, thereby can design employed deflection angle controller very simple and reliablely.

In another favourable form of implementation of the present invention, propose, the amount of this additional steering torque is limited.

Avoided such control to interfere thus, in this control was interfered, this additional steering torque was so big, to such an extent as to chaufeur may lose the control to wheel steering system.

In addition, the present invention also provides a kind of favourable device that is used to implement the method according to this invention.

The device that is used for the operator of service vehicle when stablizing vehicle, comprise the device that is used for according to the additional steering torque of additional steering torque Signal Regulation, it is characterized in that, the mechanism that is used for determining the benchmark yaw velocity is to deflection angle controller transmission benchmark yaw velocity signal, and this deflection angle controller determines that according to this benchmark yaw velocity signal and the deviation between the measured yaw velocity signal first adds the steering torque signal; Be used for determining the device of the second additional steering torque signal according to estimated tire reseting torque; Be used for trying to achieve the adder of adding steering torque from the first additional steering torque signal and the second additional steering torque signal.

A kind of favourable configuration according to the present invention, this device that is used for the operator of service vehicle when stablizing vehicle has the storage arrangement that at least one controollable is used to store the value of described benchmark yaw velocity signal, and described benchmark yaw velocity signal is by being used for determining that the device of benchmark yaw velocity is transferred to this storage arrangement.Determining that relatively control is interfered or carry out deflection angle according to this value of this benchmark yaw velocity and control between the value of the yaw velocity that these configurations can be as described above tried to achieve in the zero hour of unsettled travel conditions according to the instantaneous yaw velocity of vehicle and this reference.Can activate described storage arrangement by a starter gear.

Described starter gear can move at least two running statees, and described storage arrangement is being activated during to the second running state transition from first running state.

Can control of the transition of described starter gear by the device that is used to discern unsettled travel conditions from first running state to second running state.

Also the discriminator that can compare by the value that is used for being stored in the value of benchmark yaw velocity signal of described storage arrangement and measured Vehicular yaw cireular frequency is controlled the transition of described starter gear from second running state to first running state.

Here, described storage arrangement is transferred to described deflection angle controller with the value of the benchmark yaw velocity stored.

Determining that relatively control is interfered or carry out deflection angle according to this value of this benchmark yaw velocity and control between the value of the yaw velocity that above-mentioned these configurations can be as described above tried to achieve in the zero hour of unsettled travel conditions according to the instantaneous yaw velocity of vehicle and this reference.

According to a kind of configuration of the present invention, this device that is used for the operator of service vehicle when stablizing vehicle comprises the interference parameter observer that is used to estimate the tire reseting torque.Here especially can be by means of disturbing the parameter feedforward system to consider the tire reseting torque.

The favourable configuration according to the present invention, the described device that is used to regulate additional steering torque is servomotor, hydraulic booster steering device or the steering-by-wire formula steering hardware of electric power-assisted steering apparatus.

Description of drawings

The present invention other advantage and suitable improvement project by dependent claims and below by means of obtaining in the accompanying drawing description of a preferred embodiment.In the accompanying drawing

Fig. 1 represents to be used to try to achieve the scheme drawing of the control system of adding steering torque;

Fig. 2 represents to be used for to try to achieve the brief block diagram of control system of the additional steering torque of oversteer situation;

Fig. 3 is illustrated in being used in the block diagram shown in Fig. 2 and discerns the configuration of the piece of travel conditions;

Fig. 4 is illustrated in the configuration of the piece that comprises an enable logic unit in the block diagram shown in Fig. 2;

Fig. 5 is illustrated in being used in the block diagram shown in Fig. 2 and tries to achieve first embodiment of the piece of specified deflection angle;

Fig. 6 is illustrated in being used in the block diagram shown in Fig. 2 and tries to achieve second embodiment of the piece of specified deflection angle;

Fig. 7 is illustrated in being used in the block diagram shown in Fig. 2 and estimates first configuration of the piece of tire reseting torque;

Fig. 8 is illustrated in being used in the block diagram shown in Fig. 2 and estimates second configuration of the piece of tire reseting torque;

Fig. 9 is illustrated in being used in the block diagram shown in Fig. 2 and estimates the configuration of the piece of chaufeur steering torque;

Figure 10 represents the configuration of deflection angle controller;

Figure 11 is illustrated in being used in the block diagram shown in Fig. 2 and disturbs the configuration of the piece of parameter feedforward system;

Figure 12 represents adding the detailed view that steering torque is limited;

Figure 13 represents to be used for to try to achieve the brief block diagram of control system of the additional steering torque of understeering situation;

Figure 14 represents that being used in the block diagram shown in Figure 13 discern the configuration of the piece of travel conditions;

Figure 15 represents the configuration of the piece that comprises the enable logic unit in the block diagram shown in Figure 13;

Figure 16 represents that being used in the block diagram shown in Figure 13 try to achieve the configuration of the piece of specified steering angle;

Figure 17 represents the embodiment of deflection angle controller; And

Figure 18 represents the configuration of the piece that being used in the block diagram shown in Figure 13 limited additional steering torque.

The specific embodiment

Here be departure point with the twin shaft four-wheeled vehicle, its wheel flutter is arranged on the propons.This steering device of vehicles is preferably designed to pinion-and-rack steering device, and it is equipped with electric power-assisted steering apparatus.In the conventional operation of this servo steering device, by EPS (EPS=Electric PowerSteering, electric power steering) servomotor loads steering system with additional steering torque, and this additional steering torque strengthens the steering torque that is applied by chaufeur.At this by means of manual steering moment M _HTry to achieve chaufeur and turn to demand, measure this manual steering moment by means of the torsion bar in the deflecting bar that is installed in steering swivel system.

In order to regulate the additional steering torque request M that is used for driver assistance person _DSR(DSR=DriverSteering Recommendation, chaufeur steering recommendation) used electric power-assisted steering apparatus, controls this electric power-assisted steering apparatus at this by the interface that a controller for example passes through to the CAN bus of vehicle.As actuator, this actuator is incorporated into steering system with steering torque MDSR (DSR=Driver Steering Recommendation, chaufeur steering recommendation) to the EPS servomotor at this, and this steering torque is corresponding to restricted additional steering torque Δ M.

But the present invention also can be used for having the vehicle of other steering swivel system by similar mode, and described other steering swivel system is the steering swivel system that for example has the hydraulic booster steering device or have steering-by-wire formula steering hardware.

Show with sketch among Fig. 1 and be used to try to achieve steering torque request M _DSRThe theory structure of steering system control system 120.Travel conditions when in piece 130 and 140, discerning the unsettled motoring condition that vehicle occurs.These pieces especially use the information that provides by vehicle dynamics controller 110 at this.This vehicle-state controller 110 for example is ESP and/or ABS system.The identification of the critical travel conditions during the vehicle oversteer is preferably carried out in piece 130.The understeering of identification vehicle in piece 140.

According to the unsettled motoring condition that recognizes, in a control part of this control system, in piece 150 and 160, calculate specified steering angle sigma _Soll, determine this specified deflection angle in the mode that is complementary with the travel conditions that identifies.

When recognizing the oversteer that can cause by load variations in the bend or braking procedure, in piece 150, calculate and make the stable specified steering angle sigma of motoring condition as far as possible apace _Soll

Travel conditions during the vehicle understeering usually can be when car speed be high and on the road surface with low friction coefficient, for example on by ice-covered road surface or occur in the water skiing situation.Divertical motion can not influence or only influence very littlely the weaving of vehicle in this situation usually.But when changing to high friction coefficient by low friction coefficient, the divertical motion of chaufeur causes the vigorous reaction of not expecting for chaufeur of vehicle and causes breakking away.Therefore in understeering, regulate deflection angle that exist, that in piece 160, determine when purpose is to remain on the identification situation.

Preferably disturb the deflection angle controller 170 of parameter feedforward to determine additional steering torque Δ M therein, determine auxiliary torque M by this additional steering torque _DSR, by means of this auxiliary torque, chaufeur can cosily be regulated specified steering angle sigma _SollIn the understeering situation, additional steering torque Δ M reacts on described divertical motion, so that driver assistance person keeps instantaneous deflection angle.In the case also can be by the parameter of piece 150 and 160 transmission control units 170, coefficient of amplification or disturb parameter for example is so that control in different travel conditions with suitable manner.

In piece 180, additional steering torque Δ M is limited according to situation.Thus, this additional steering torque Δ M especially is limited in allowing chaufeur to carry out value with the inconsistent divertical motion of predetermined value of control system 120.Chaufeur all keeps the control fully to vehicle thus at any time.

The described part of implement regulating in the oversteer situation of control system 120, a preferred configuration that promptly especially comprises the part of piece 130,150,170 and 180 in the principle view of Fig. 1 illustrate with a sketch that is expressed as block diagram in Fig. 2.

This subsystem especially comprises the piece 210 that is used to discern the oversteer situation at this, also comprises the piece 220 with the decision circuit that is used to start described control system, is used for for example estimating particularly tire reseting torque M _RAnd chaufeur steering torque M _FThe piece 230 of interference parameter, be used for determining specified steering angle sigma _SollPiece 240, deflection angle controller 250 is used to disturb the piece 260 of parameter feedforward, and the piece 270 that is used to limit additional steering torque Δ M.Confined additional steering torque Δ M at this corresponding to the steering torque request M on the EPS servomotor _DSR

The favourable configuration of piece 210 that is used to discern the oversteer situation is shown in Figure 3.Datum velocity v when vehicle _RefGreater than a predetermined threshold value S _vAnd when at least one was satisfied in following described other condition, the oversteer situation was identified in piece 210.Threshold value S _vAt this for example between 5km/h and 20km/h, preferably at 10km/h.

When

A) steering angle sigma on the wheel flutter _RHave and measured yaw velocity

The benchmark yaw velocity that coexists and calculated in the vehicle benchmark model Between poor Identical symbol,

B) this is poor

Greater than a predetermined threshold value S _ψ, and

C) the SESP zone bit has value 1,

The time, first additional conditions that are used to discern the oversteer situation are satisfied.

A) guaranteed that unsettled travel conditions is the unsettled motoring condition of oversteer situation and other form in this condition by described condition.According to condition b) pass judgment on instantaneous travel conditions and whether have critical motoring condition.Threshold value S _ψPreferably with instantaneous vehicle datum velocity v _RefReach instantaneous current friction coefficient and be complementary, wherein for example can be based on the friction coefficient of in the ESP system, estimating at this.Preferably carry out described coupling by means of characteristic curve or form.

The SESP zone bit determined by another travel conditions means of identification, if detect during straight-line travelling or negotiation of bends brake snub or during negotiation of bends load variations, then this SESP zone bit value is 1.Otherwise value is 0.

At this by means of the steering angle sigma on the wheel flutter of vehicle _RAnd the rate of change of this deflection angle

And by means of the measured transverse acceleration a of vehicle _yAnd the identification vehicle is straight-line travelling or travels in bend under the situation of the recognition result of considering the ESP system.

In addition, discern vehicle by means of the brake-pressure in the car side brake and brake-pressure distribution in time and whether can produce fugitiveness by the brake intervention of chaufeur.

In addition, discern whether can produce fugitiveness by means of measured wheel velocity and by means of motor torque and distribution in time thereof or by means of accelerator pedal position and distribution in time thereof because of chaufeur reduces motor torque apace.

In addition, determine the SESP zone bit by means of oversteer trend, this oversteer trend is by means of yaw velocity And rate of change is tried to achieve.In addition, coordinate in order to interfere mutually with ABS-control, whether the trailing wheel of check vehicle is in the ABS control.

When

A) rate of change of angle of side slip β Greater than predetermined threshold value S _β, and

B) steering angle sigma _RRate of change

Greater than predetermined threshold value S _δ,

The time, second additional conditions that are used to discern the oversteer situation are satisfied.

Discerned the oversteer situation that when chaufeur quickens, especially in the vehicle that postposition drives, produces thus in bend ahead of time.Threshold value S _βAnd S _δCoordinate mutually with cooresponding vehicle in running test at this.

If in piece 210, recognize the oversteer situation, then represent oversteer zone bit value of being changed to 1 of the output signal of this piece 210 by means of described condition.If described condition no longer is satisfied, then this oversteer zone bit is from being worth 1 value of resetting to 0.But preferred at this based on less threshold value, feasiblely stablize described control by hysteresis.

This oversteer zone bit is as the incoming signal of piece 220, and this piece comprises the enable logic unit that is used for described control.The favourable configuration of this piece is shown in Figure 4.

When igniting restarts, representing oversteer effective marker position value of being changed to 0 of the output signal of piece 220.If this oversteer zone bit value is 1, the then variation of the value of proceeding to 1.

In piece 220, by memory device 410 of this oversteer effective marker position control, this memory device is preferably configured as the maintenance energy disperser of edge control.If the value of this oversteer effective marker position is at moment t _EinChange to 1 from 0, then with the benchmark yaw velocity

Value

Be stored in this memory device 410.The benchmark yaw velocity

This value this expression vehicle at moment t _EinThe feature of the stabilized conditions when entering described control can be interfered by control and be recovered this stabilized conditions.

If this oversteer effective marker position has value 1, then when at least one is satisfied in the following conditions, this value value of resetting to 0:

A) the oversteer zone bit has value 0 (perhaps its value changes to 0 from 1),

B) steering angle sigma _RSymbol and measured Vehicular yaw cireular frequency

The symbol difference (perhaps with yaw velocity

Symbol compare this steering angle sigma _RSymbol change has taken place),

C) measured yaw velocity

Absolute value less than the benchmark yaw velocity Value

(perhaps being reduced under this value of benchmark yaw velocity).

According to condition a),, then stopping (zur ü cknehmen) described control if no longer there is the oversteer situation interferes.When chaufeur during in the reaction action very tempestuously and exceedingly of described control period, condition b) be satisfied.The critical travel conditions of Chu Xianing causes that at this ESP-control interference is so that vehicle stabilization therefrom.For the deflection angle avoiding at this being examined or check regulate with ESP-control interference between coordination problem, this oversteer zone bit is in this value of resetting to 0.

According to condition c), if vehicle is stable, then cancel deflection angle control.This with the value

Rather than with the benchmark yaw velocity Instantaneous value characterize stable motoring condition for the basis so that avoid influencing each other of deflection angle control and ESP control once more.

This influence produces in this wise, i.e. the benchmark yaw velocity

Influenced by the divertical motion of chaufeur, this chaufeur carries out this divertical motion based on described by means of additional steering torque Δ M auxiliary.Because value and the benchmark yaw velocity of additional steering torque Δ M

Value between influence each other and can strengthen the yaw velocity deviation of vehicle, can cause the benchmark yaw velocity thus Amplitude vibration with continuous increase.The ESP system control corresponding that reaches by the deflection angle control setup is interfered, and can cause vehicle " shaking " at this.

But by interrupt condition c) can realize stable control, in described stable control, can avoid described coordination problem.

In addition, in an advantageous embodiments of the present invention, when estimated by chaufeur steering torque that chaufeur applied Less than threshold value S _MThe time, the oversteer zone bit is the value of resetting to 0 also.Situation when this no longer grips bearing circle by means of this condition identification of driver.This is identified in this must be with chaufeur steering torque M _FEstimated valve

Be the basis because in steering system measured manual moment M _HThe influence that the control that carried out by the EPS servomotor is interfered.In piece 230, estimate chaufeur steering torque M in the case _F

In order to determine specified steering angle sigma _Soll-in the adjusting of this specified deflection angle, to be provided with piece 240 by described control driver assistance person.A preferred embodiment of this piece has been shown among Fig. 5, and this preferred embodiment is with the time-optimized basis that is controlled to be.

In this embodiment, at first from measured Vehicular yaw cireular frequency

With at moment t _EinThe benchmark yaw velocity of determining

Between deviation

Try to achieve specified additional deflection angle Δ δ _RSpecified steering angle sigma _SollObtain from following formula by subtraction:

δ _Soll＝δ _R-Δδ _R

Provide the benchmark yaw velocity by a memory device 510, this memory device also is preferably designed so that the maintenance energy disperser of edge triggering and passes through described oversteer effective marker position control/actuating.

Auto model with an oversteer is that this additional deflection angle Δ δ is tried to achieve on the basis _R, in this model, the yaw velocity deviation

Along with additional deflection angle Δ δ _RIncrease and increase.Especially here select to have following transfer function $G\left(s\right)=L\{\stackrel{.}{\mathrm{\ψ}}-{\stackrel{.}{\mathrm{\ψ}}}_{\mathrm{ref}}\left(t_{\mathrm{ein}}\right)\}/L\{\mathrm{\Δ}{\mathrm{\δ}}_R\}$ Model, wherein L{.} represents Laplace transform:

$G\left(s\right)=\frac{K}{s(1+\mathrm{sT})}$

Based on this model by the input parameter $e={\stackrel{.}{\mathrm{\ψ}}}_{\mathrm{ref}}\left(t_{\mathrm{on}}\right)-\stackrel{.}{\mathrm{\ψ}}$ With parameter

Between difference determine control parameter u, in switching line (Schaltlinie) 520, try to achieve this parameter

Have at this:

$S\left(\stackrel{.}{e}\right)=-T\stackrel{.}{e}+K{\mathrm{\δ}}_{\max }T\ln (1+\frac{\left|\stackrel{.}{e}\right|}{{\mathrm{K\δ}}_{\max }})\mathrm{sgn}\left(\stackrel{.}{e}\right)$

The preferred linearizing form of using switching line 520 in the case wherein has:

$S\left(\stackrel{.}{e}\right)\≈-0.31T\stackrel{.}{e}$

Parameter T for example can mate in running test.

In piece 530, realize additional deflection angle Δ δ by means of three dot characteristics curves _RDetermine.Value δ _MaxDetermine additional deflection angle Δ δ at this _RMaximum magnitude.In addition, only transmit the control parameter u of absolute value by piece 530 greater than insensitiveness parameter a.This measure is used to stablize described control.

Be used for determining specified steering angle sigma _SollAnother preferred embodiment of piece 240 shown in Figure 6.At this, specified additional deflection angle Δ δ _RBy by means of factor K _βThe angle of side slip speed of amplifying

And by means of factor K _ψThe measured Vehicular yaw cireular frequency that amplifies

With the benchmark yaw velocity

Between deviation

And determine.Arbitrate (Arbitrierung) at this in piece 610, this arbitration is preferably by means of realizing to described 610 input parameter summation or by means of forming maxim.

Specified steering angle sigma _SollIn this embodiment also as the steering angle sigma on the wheel flutter _RWith the steering angle change amount Δ δ that is tried to achieve _RBetween difference determine.

The task of the piece 230 among Fig. 2 is, to acting on the tire reseting torque M on the steering system _RAnd the manual steering torque M of chaufeur that applies by chaufeur _FEstimate that this tire reseting torque is by the side direction guidance force (Seitenf ü hrungskraft) of tire and transverse force causes and to manual steering torque M _HActing in opposition.In order to carry out this estimation, in a preferred embodiment of the present invention, use linear interference parameter sight cell at this.

Being used to shown in Fig. 7 estimated tire reseting torque M _RInterference parameter observer at this model equation below steering swivel system:

${\stackrel{..}{\mathrm{\δ}}}_L=\frac{1}{J}(\frac{i_M}{i_L}{M}_M+M_H-M_{\mathrm{IR}}-M_R)---\left(1\right)$

Represent the rotor inertia of steering system, M at this J _MThe steering torque that expression is applied by the EPS servomotor, described steering torque for example can be tried to achieve i by the received current of this motor _L=δ _L/ δ _RSteering angle sigma on the Steering gear of expression vehicle _LWith the steering angle sigma on the wheel flutter _RBetween transmitting ratio, i _M=δ _M/ δ _ROperating angle (Aussteuerungswinkel) δ of expression EPS servomotor _MWith the steering angle sigma on the wheel flutter _RBetween transmitting ratio.Described analyzing and processing of carrying out by means of equation 1 is relevant with Steering gear.By the moment M in the equation 1 _IRSteering system in-to-in and deflection angle speed have been considered

The reseting torque (spring effect) that proportional viscous friction and steering system in-to-in and deflection interrelate, described viscous friction is owing to produce described reseting torque and steering angle sigma in lubricated lip-deep slip _LProportional.Moment M _IRHave following form thus:

$M_{\mathrm{IR}}={\mathrm{<figure-callout\; id="1"\; label="c"\; filenames="C20048003579100291.png,C20048003579100301.png"\; state="\{\{state\}\}">c</figure-callout>}}_1{\mathrm{\&delta;}}_L+{\mathrm{<figure-callout\; id="1"\; label="d"\; filenames="C20048003579100291.png,C20048003579100301.png"\; state="\{\{state\}\}">d</figure-callout>}}_1{\stackrel{.}{\mathrm{\&delta;}}}_L---\left(2\right)$

Constant of proportionality c ₁And d ₁Also can as rotor inertia J, in running test, try to achieve.

By means of equation 1, disturb the parameter observer to calculate the deflection angle acceleration/accel of estimation

Obtain deflection angle speed thus by first integral

The value of an estimation

Another integration is by the deflection angle speed of this estimation

The deflection angle of estimation is provided

In disturbing the parameter observer by estimated deflection angle

With measured steering angle sigma _LBetween deviation and by estimated deflection angle speed

With the deflection angle speed that derives from the observed reading of steering angle sensor Between deviation try to achieve tire reseting torque M _REstimated valve

Time derivative

Described deviation feeds back to the input end that disturbs the parameter observer by amplification matrix L.Therefore have:

${\stackrel{\stackrel{.}{^}}{M}}_R=L_{31}({\mathrm{\&delta;}}_L-{\widehat{\mathrm{\&delta;}}}_L)+L_{32}({\stackrel{.}{\mathrm{\&delta;}}}_L-{\stackrel{\stackrel{.}{^}}{\mathrm{\&delta;}}}_L)$

Also can be by amplification matrix L directly by means of estimated amount

With

With the amount δ that tries to achieve from measurement signal accordingly _LWith

Between deviation mate estimated deflection angle acceleration/accel

And estimated deflection angle speed

Can use the standard method of control theory to design the coefficient of amplification L of amplification matrix L _IjThese coefficient of amplifications can be tried to achieve by POLE PLACEMENT USING (Polvorgabe).

In another preferred embodiment of the present invention, propose, use and estimate tire reseting torque M according to the nonlinear interference parameter observer of Fig. 8 _R

This estimation is at this model based on steering system, the static friction that has produced when also having considered the employed parameter to slide on the contact surface of drying in this model in above-mentioned model.Version below the internal turn moment that forms by rubbing adopts in this model:

$M_{\mathrm{IR}}=K_F{\mathrm{\&delta;}}_L+K_D{\stackrel{.}{\mathrm{\&delta;}}}_L+K_C\mathrm{sgn}\left({\stackrel{.}{\mathrm{\&delta;}}}_L\right)---\left(3\right)$

Observer shown in Fig. 8 is brought in this model equation according to the interior steering torque of equation 4 again based on model equation 1.Estimated deflection angle speed

And estimated deflection angle

This also by integration from estimated deflection angle acceleration/accel

Try to achieve:

${\stackrel{\stackrel{.}{^}}{\mathrm{\&delta;}}}_L=\&Integral;{\stackrel{\stackrel{..}{^}}{\mathrm{\&delta;}}}_L\mathrm{dt}$ And ${\widehat{\mathrm{\&delta;}}}_L^{\&prime;}=\&Integral;{\stackrel{\stackrel{.}{^}}{\mathrm{\&delta;}}}_L\mathrm{dt}$

At this from estimated deflection angle speed

With measured deflection angle speed Between difference and from estimated deflection angle

With measured steering angle sigma _LBetween difference obtain tire reseting torque to be estimated

And it is fed back to the input end that disturbs the parameter observer:

${\hat{M}}_R={\mathrm{<figure-callout\; id="1"\; label="h"\; filenames="C20048003579100291.png,C20048003579100301.png"\; state="\{\{state\}\}">h</figure-callout>}}_1\&CenterDot;({\stackrel{\stackrel{.}{^}}{\mathrm{\&delta;}}}_L-{\stackrel{.}{\mathrm{\&delta;}}}_L)+{\mathrm{<figure-callout\; id="2"\; label="h"\; filenames="C20048003579100321.png"\; state="\{\{state\}\}">h</figure-callout>}}_2\&CenterDot;({\widehat{\mathrm{\&delta;}}}_L-{\mathrm{\&delta;}}_L)$

Magnification factor h ₁And h ₂Suit in running test, to determine that this system stablizes and can enough accurately estimate the value M of tire reseting torque especially thus at this _R

Estimated tire reseting torque Corresponding to the load moment M that acts on the steering system _LastBy with a factor i _LMultiply each other and to make the load moment M that determines relatively with deflecting bar _LastWheel flutter with vehicle interrelates.

Preferably with the tire reseting torque

The similar mode of estimation carry out chaufeur steering torque M by means of the interference parameter observer of a linearity shown in Fig. 9 _FEstimation.This interference parameter observer is at this model equation based on following bearing circle rotating property, especially the chaufeur steering torque M that will be applied by chaufeur _FWith measured manual steering moment M _HBetween difference introduce in this model equation:

${\stackrel{..}{\mathrm{\&delta;}}}_L=\frac{1}{J}(M_F-M_H-{\mathrm{<figure-callout\; id="2"\; label="c"\; filenames="C20048003579100321.png"\; state="\{\{state\}\}">c</figure-callout>}}_2{\mathrm{\&delta;}}_L-{\mathrm{<figure-callout\; id="2"\; label="d"\; filenames="C20048003579100321.png"\; state="\{\{state\}\}">d</figure-callout>}}_2{\stackrel{.}{\mathrm{\&delta;}}}_L)---\left(4\right)$

By item

Viscous friction and spring effect have also been considered.

In order to calculate estimated chaufeur steering torque by means of equation 4 Used estimated deflection angle acceleration/accel again

Estimated deflection angle speed

And the estimated deflection angle on the bearing circle

With the estimated tire reseting torque among Fig. 7

Time derivative

Similar, estimated chaufeur steering torque

Time derivative

Disturb in the parameter observer from estimated deflection angle at this

With measured steering angle sigma _LBetween deviation and from estimated deflection angle speed

With the deflection angle speed that derives from the observed reading of steering angle sensor

Between deviation try to achieve, described deviation feeds back to the input end of this interference parameter observer by amplification matrix l.Therefore have:

${\stackrel{\stackrel{.}{^}}{M}}_F=l_{31}({\mathrm{\&delta;}}_L-{\widehat{\mathrm{\&delta;}}}_L)+l_{32}({\stackrel{.}{\mathrm{\&delta;}}}_L-{\stackrel{\stackrel{.}{^}}{\mathrm{\&delta;}}}_L)$

Obtain estimated chaufeur steering torque thus by integration

As already described, from estimated chaufeur steering torque

Can know whether chaufeur has unclamped bearing circle during control is interfered.

Try to achieve additional steering torque Δ M by means of the control of the deflection angle in the piece 250 and by means of the interference parameter feedforward of implementing by piece 260.

The block diagram of preferred controller 250 has been shown among Figure 10.The control component M of additional steering torque Δ M _RegThis shown in the form of implementation of regulating control 250 in by first component and second component and determine.

This first component is by using the pre-factor K of determining by means of proportional regulator ₂To specified steering angle sigma _SollSteering angle sigma with instantaneous existence on the pivoted wheels on vehicle _RBetween the adjusting deviation amplify to determine.

This second component is by deflection angle speed

The adjusting deviation obtain, and in the branch road of the controller 250 that is designed to cascade controller, be determined.The instruction parameter that is used for internal controller is at this adjusting deviation δ by described deflection angle _Soll-δ _RWith the pre-factor K of determining _lMultiply each other and try to achieve, and corresponding to specified steering angle change amount.This adjusting deviation is correspondingly by specified steering angle change amount of being tried to achieve and the deflection angle speed of being determined by the observed reading of steering angle sensor

Between poor

Obtain.

The internal controller of described cascade controller is preferably designed to PD (proportion differential) controller, thus, and the following control component M that obtains additional steering torque _RegSecond component:

${\mathrm{<figure-callout\; id="2"\; label="K"\; filenames="C20048003579100321.png"\; state="\{\{state\}\}">K</figure-callout>}}_{2,P}[{\mathrm{<figure-callout\; id="1"\; label="K"\; filenames="C20048003579100291.png,C20048003579100301.png"\; state="\{\{state\}\}">K</figure-callout>}}_1\&CenterDot;({\mathrm{\&delta;}}_{\mathrm{Soll}}-{\mathrm{\&delta;}}_R)-{\stackrel{.}{\mathrm{\&delta;}}}_R]+{\mathrm{<figure-callout\; id="2"\; label="K"\; filenames="C20048003579100321.png"\; state="\{\{state\}\}">K</figure-callout>}}_{2,D}\&CenterDot;\frac{d}{\mathrm{dt}}[{\mathrm{<figure-callout\; id="1"\; label="K"\; filenames="C20048003579100291.png,C20048003579100301.png"\; state="\{\{state\}\}">K</figure-callout>}}_1\&CenterDot;({\mathrm{\&delta;}}_{\mathrm{Soll}}-{\mathrm{\&delta;}}_R)-{\stackrel{.}{\mathrm{\&delta;}}}_R]$

If specified steering angle sigma _SollWith instantaneous steering angle sigma _RBetween difference because the divertical motion of chaufeur increases, then described system can be by means of the control component M of additional steering torque _RegThis second component interfere very fast and effectively.

The component of additional steering torque Δ M

By using factor K _SThe load steering torque M of the estimation of amplifying _LastObtain, and in piece 260, determine, shown in the block diagram of this piece in Figure 11.To component Consideration be equivalent to disturb parameter feedforward at this, but this interferences parameter feedforward makes road pavement feature consider at this, does not carry out deflection angle and controls but can rely on this influence in simple mode.In order to determine additional steering torque Δ M, with component M _RegWith

Addition.Should and also multiply each other with the oversteer effective marker position of determining by the enable logic unit in the piece 220, thus, this additional steering torque has only just be transferred to the EPS servomotor when this oversteer effective marker position has value 1.

In addition, in piece 270, this additional steering torque is limited.Offer some clarification on the favourable configuration of this piece by means of Figure 12.

At first should control the power of interfering at this by additional steering torque Δ M and deflection angle speed calculation

If the absolute value of this power surpasses predetermined value P _{Δ M, max}, then by the auxiliary torque M of EPS servomotor to the steering system loading _DSRBe limited in following value:

$M=\frac{P_{\mathrm{\&Delta;M},\max }}{\max (1,|{\stackrel{.}{\mathrm{\&delta;}}}_R\left|\right)}\mathrm{sgn}\left(\mathrm{\&Delta;M}\right)$

If situation is not so, then to the steering torque request M of EPS servomotor _DSRCorresponding to additional steering torque Δ M.

Especially when having cancelled chaufeur right and whether unclamped the identification that bearing circle carries out, described restriction is significant especially.

The preferred embodiment of implementing the part of control in the understeering situation of this control system has been shown in the sketch with block representation in Figure 13.

This subsystem especially comprises at this: be used for piece 1310 that lack of identification turns to situation, be used to start the decision circuit of described control system piece 1320, be used for determining specified steering angle sigma _SollPiece 1330, deflection angle controller 1340, and the piece 1350 that is used to limit additional steering torque Δ M.

Illustrated among Figure 14 and be used for the favourable form of implementation that lack of identification turns to the piece 1310 of situation.Datum velocity v when vehicle _RefGreater than predetermined, between 60km/h and 120km/h, preferably at the threshold value S of 80km/h _v, and when at least one is satisfied in the condition described below additionally, in piece 1310, recognize the understeering situation:

A) the water skiing zone bit has value 1.

B) coefficientoffriction of the instantaneous existence of ground-surface is less than predetermined threshold value S _μ

If the ESP system identification is to the water skiing situation, then this water skiing zone bit is preferably by ESP system value of being changed to 1 of vehicle.As the instantaneous value μ of surface friction coefficient, preferably also adopt value by the ESP system estimation.The threshold value S of coefficientoffriction _μFor example between 0.05 and 0.2, preferably 0.1.

If in piece 1310, recognize the understeering situation, then represent understeering zone bit value of being changed to 1 of the output signal of piece 1310.If do not recognize the understeering situation by means of above-mentioned condition, then the understeering zone bit has value 0.

This understeering zone bit incoming signal that acts on piece 1320, this piece comprises the enable logic unit that is used for described adjusting.A preferred configuration of piece 1320 has been shown among Figure 15.

When igniting restarts, be value 0 with understeering effective marker position by described.If this understeering zone bit value is 1, then proceed to from being worth 0 variation to value 1.

When this understeering zone bit value was 0, if described oversteer effective marker position has value 1, then this oversteer effective marker position reset to 0.

In piece 1330, try to achieve specified steering angle sigma _Soll, this specified deflection angle will be assisted by means of described control by the adjusting of chaufeur.The preferred form of implementation of piece 1330 has been shown among Figure 16.

Piece 1330 comprises memory device 1610 at this, and this memory device is preferably designed to the maintenance energy disperser of edge triggering, and by the control of described oversteer effective marker position.If this oversteer effective marker position is at moment t _EinFrom being worth 0 value of changing to 1, the steering angle sigma on the wheel flutter of vehicle then _RAt moment t _OnThe value δ that exists _R(t _Ein) be stored in this memory device 1610, and as specified steering angle sigma _SollBy piece 1330 outputs.

By control component M _RegMultiply each other to determine additional steering torque Δ M with described understeering effective marker position, and thus when this understeering effective marker position has value 1, described additional steering torque value M _RegOtherwise should have value 0 by additional steering torque Δ M.

Should add the control component M of steering torque Δ M _RegDetermine by controller 1340.The advantageous embodiments of this controller has been shown among Figure 17.

Described control component is in this embodiment by the deviation δ that amplifies _Soll-δ _RWith the deflection angle speed of amplifying

Between difference determine.

At this by means of the characteristic curve u in piece 1710 and 1720 _p(δ _Soll-δ _R) and

Try to achieve coefficient of amplification.Determine deflection angle speed by means of derivative element 1730 This derivative element is realized by suitable actual differentiator.Preferred this derivative element 1730 is DT ₁Link.

Restriction to additional steering torque Δ M is set in addition, and described restriction depends on instantaneous motoring condition and instantaneous driving behavior carries out.The block diagram of limiting part has been shown among Figure 18.

The restriction of execution and velocity correlation is wherein carried out than restriction stronger in the moderate velocity scope described additional steering torque in lower speed range in piece 1810.Verified, a lot of vehicle operators think that such and restriction velocity correlation are comfortable especially.The restriction of in high speed range described additional steering torque being strengthened, because here when the aberration of vehicle operators takes place, interference can cause severe impairment.Preferably carry out restriction in the piece 1810 by means of characteristic curve, this characteristic curve is for example determined in running test.

The time length that piece 1820 is interfered with control is elongated to reduce additional steering torque.Prevent thus: parameter-for example the brake-pressure time error constantly increases owing to determine input, perhaps since evaluated error constantly increase-for example in travelling by the braking procedure during the bend to direction of traffic angle (Kurslenkwinkel) when estimating, have error ground to carry out described control and interfere.Usually, if warn the dangerous situation of vehicle operators and guide its stable vehicle after the described interference certain time, then described operator can take over fully and turn to control task.

Also imagined the restriction of the behavior of having considered vehicle operators in addition.At this, in piece 1830 from the measured manual steering moment M that applies by chaufeur _HAnd the instantaneous adjusting deviation of deflection angle is tried to achieve: whether this vehicle operators follows the indication of this control system, and perhaps whether he disobeys these indications.In the case can be by ongoing in time observation of described parameter and analyzing and processing are formed such parameter, this parameter is the yardstick that is used for the described disobedience of (measurement) chaufeur.If this parameter surpasses predetermined threshold value, then additional steering torque is by piece 1830 values of being reduced to 0.

In addition, carry out the dynamic characteristics restriction in piece 1840, increase or reduction to additional steering torque in described dynamic characteristics restriction limit, so that avoid additional steering torque to be applied on the bearing circle apace.If there is not this restriction, under the very high situation of the dynamic characteristics of EPS servomotor, may be owing to the unexpected introducing (Einsteuern) of additional steering torque bearing circle be beaten from the vehicle operators hand and take off.

Output signal in the described limiting part is the steering torque request M to the EPS servomotor _DSRIn the understeering situation, steering torque M _DSRDriver assistance person avoids unexpected deflection angle to change, and has avoided the sideslip of vehicle when changing to great friction coefficient thus.

Claims (19)

1. method that is used for the operator of service vehicle when stablizing vehicle, load with the steering system of additional steering torque in the method vehicle, it is characterized in that: first component of determining described additional steering torque according to the instantaneous deflection angle on the wheel flutter of vehicle and the deflection angle deviation between the specified deflection angle, wherein determine described deflection angle deviation according to the deviation between the value of the instantaneous value of the yaw velocity of vehicle and benchmark yaw velocity, and wherein in an auto model, try to achieve the value of described benchmark yaw velocity by the value of the predetermined parameter of chaufeur according at least one, wherein, determine a second component of described additional steering torque according to the estimated valve of tire reseting torque, try to achieve described additional steering torque by first component and second component addition.

2. according to the method for claim 1, it is characterized in that, try to achieve described benchmark yaw velocity according to the deflection angle of regulating by vehicle operators.

3. according to the method for claim 1, it is characterized in that, in the time of under the absolute value of the instantaneous yaw velocity of vehicle drops to the value of trying to achieve zero hour at unsettled travel conditions of described benchmark yaw velocity, cancel described additional steering torque.

4. according to the method for claim 1, it is characterized in that, deviation according to the value of the instantaneous yaw velocity of vehicle and described benchmark yaw velocity is determined described deflection angle deviation, and the value of described benchmark yaw velocity is to try to achieve in the zero hour of unsettled travel conditions.

5. according to the method for claim 3 or 4, it is characterized in that, determine the described zero hour of unsettled travel conditions by the enable logic unit.

6. according to the method for claim 5, it is characterized in that the result of described enable logic unit access travel conditions means of identification is to determine the beginning of unsettled travel conditions.

7. according to each method of claim 1 to 4, it is characterized in that, by disturbing the parameter observer to estimate described tire reseting torque.

8. according to each method of claim 1 to 4, it is characterized in that, the amount of described additional steering torque is limited.

9. device that is used for the operator of service vehicle when stablizing vehicle, this device comprises the device that is used for according to the additional steering torque of additional steering torque Signal Regulation, it is characterized in that, one is used for determining that the device of benchmark yaw velocity is transferred to the deflection angle controller with benchmark yaw velocity signal, and this deflection angle controller determines that according to this benchmark yaw velocity signal and the deviation between the measured yaw velocity signal first adds the steering torque signal; Be used for determining the device of the second additional steering torque signal according to estimated tire reseting torque; Be used for trying to achieve the adder of adding steering torque from the first additional steering torque signal and the second additional steering torque signal.

10. according to the device of claim 9, it is characterized in that, this device that is used for the operator of service vehicle when stablizing vehicle has the storage arrangement that at least one controollable is used to store the value of described benchmark yaw velocity signal, and described benchmark yaw velocity signal is by being used for determining that the device of benchmark yaw velocity is transferred to this storage arrangement.

11. the device according to claim 9 or 10 is characterized in that, activates described storage arrangement by a starter gear.

12. the device according to claim 11 is characterized in that, described starter gear can move at least two running statees, and described storage arrangement is being activated during to the second running state transition from first running state.

13. the device according to claim 12 is characterized in that, controls the transition of described starter gear from first running state to second running state by the device that is used to discern unsettled travel conditions.

14. device according to claim 12, it is characterized in that, control of the transition of described starter gear from second running state to first running state by the discriminator that the value that is used for being stored in the value of benchmark yaw velocity signal of described storage arrangement and measured Vehicular yaw cireular frequency compares.

15. the device according to claim 10 is characterized in that, described storage arrangement is transferred to described deflection angle controller with the value of the benchmark yaw velocity stored.

16. the device according to claim 9 or 10 is characterized in that, this device that is used for the operator of service vehicle when stablizing vehicle comprises the interference parameter observer that is used to estimate the tire reseting torque.

17. the device according to claim 9 or 10 is characterized in that, the described device that is used to regulate additional steering torque is the servomotor of electric power-assisted steering apparatus.

18. the device according to claim 9 or 10 is characterized in that, the described device that is used to regulate additional steering torque is the hydraulic booster steering device.

19. the device according to claim 9 or 10 is characterized in that, the described device that is used to regulate additional steering torque is a steering-by-wire formula steering hardware.

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